Question on Ammeters...

I have two alternators (I am using Bob's Z-13/8 design with a primary and backup), so does the AF-4500 have two ammeter displays one for each alternator?

Thanks,

Matt

The AF-4500 will support and display two current sensors. One sensor will need to be the Hall Effect type. See page 82 of the version 7.4 AF-4500 manual that is currently posted.

After configuration (and calibration) the display under AMP will two narrow bars, one for each current sensor. The numeric display under the narrow bars switches between the two sensors about once per second.

I have a Plane Power 60A alternator for the primary alternator and a SD-20 for the backup alternator in my RV-7A. Current draw is easy to read.

Regards,

Roy

Thanks Roy.

Alternately, you can run both alternator B leads through the hall effect current sensor. With the Nuckols designs, only one alternator is operational at any one time anyway. I did it this way and saved quite a few pounds and interconnects. Works great, less filling.

Noah,

Is the Amp Transducer pictured on Page 82 mounted on the cabin or engine side of the firewall? Also, you setup is exactly like mine, do you have any pictures or a build log website?

Thanks,
Matt

Since I built a tractor configuration airplane (engine in front) with the battery firewall forward, it didn't make sense to route the alternator B-leads thru the firewall to go through this sensor, then back forward through the firewall to the battery. I would suspect that most airplanes are similarly configured with the battery forward of the firewall, which makes me wonder why AFS doesn't supply a more robust sensor that is rated for the FF environment. The hall effect current sensor is rated for a very low temperature, I think around 120F - check Honeywell's website for the spec sheet.

Anyway, mine is mounted to the firewall with standoffs, and the B-Leads are strain relieved right next to the sensor. Here is a photo taken during construction, don't have one of the final product, but this should tell you what you need to know.

http://www.freeimagehosting.net/t/rzw8g.jpg

Noah,
I have a setup which sounds similar to yours, RV8A with battery etc firewall forward and using Bob's Z13/8 architecture.
Has your setup (single Hall Effect with both 'B' leads running through a firewall forward mounted sensor) been successful.
If not, what recommendation would you make for my setup which I am wiring now?
Cheers
Cliff Princehorn
Lake Macquarie
Australia.

Hi Cliff. Running both b leads thru the hall effect sensor has worked fine for me. I would do it again.

Best, Noah

Thanks Noah,
Very reassuring.
Cheers Cliff